A dynamic IP doesn't necessarily mean your IP changes each time you connect, this behaviour is particular to your ISP's policy. Dynamic IPs can remain the same for months. Static and dynamic IP addresses are defined by how they are assigned to your PC by your ISP.
If your ISP had to assign you your IP either by phone or mail and you had to activate it yourself within windows, then you have a static IP, otherwise you have a dynamic IP.
edit: bad grammar![]()
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